In a refrigerant cycle, a refrigerant liquid condensed in the condenser is depressurized by an expansion valve to become a gas-liquid two-phase state fluid in which the refrigerant vapor and the refrigerant liquid is mixed and flows into an evaporator. When the refrigerant flows into the evaporator in the gas-liquid two phase state, the pressure loss of the refrigerant when passing through the evaporator is large, resulting in the decrease in the energy efficiency of the air conditioner.
Therefore, the energy efficiency of the air conditioner can be improved by separating the refrigerant into the refrigerant vapor and the refrigerant liquid through the use of a gas-liquid separator before the refrigerant flows into the evaporator so that only the refrigerant liquid flows through the evaporator to decrease the pressure loss generated when the refrigerant passes through the evaporator.
In the conventional gas-liquid separator, the inlet pipe and the outlet pipe are disposed in the upper portion of the vessel, the diameter of the inlet pipe is made smaller toward the lower end of the inlet pipe, and a discharge hole is provided in a side face of the inlet pipe, thus manufacturing time is shortened as compared to the arrangement in which the inlet pipe is mounted to the side face of the vessel (see Patent Document 1, for example).
Patent Document 1: Japanese Patent No. 3,593,594